The value of intraoperative ultrasound during hepatic resection compared with improved preoperative magnetic resonance imaging

Background: Patients with colorectal metastases confined to the liver may be cured by resection. Combined bimanual palpation and intraoperative ultrasound (IOUS) augment the detection of colorectal hepatic metastases. The importance of IOUS in the surgical management of hepatic tumors has been demonstrated and should arguably be considered the final diagnostic procedure. Objective: To determine the relevance of routine IOUS prior to hepatic resection compared with improved preoperative Magnetic resonance imaging (MRI). Patients and methods: Eighty patients with metastatic colorectal adenocarcinoma underwent hepatic resection between 1998 and 2001. The IOUS results were compared with preoperative MRI, bimanual palpation, and resection histopathology. The preoperative surgical plan was compared with the surgical procedure performed. Data were retrospectively analyzed. Results: IOUS provided additional useful information not available preoperatively for 37 (47%) patients, including the identification of subcentimetre metastatic lesions, characterization of the lesion, and the anatomy of the hepatic vasculature. The preoperative surgical plan was changed secondary to the IOUS findings alone in 14/80 (18%) patients. IOUS did not provide any additional useful information for 43 (53%) patients. A correlation was demonstrated between the preoperative diagnosis, intraoperative findings, and resection histopathology. Conclusion: Accurate diagnostic studies facilitate critically decisive actions during planned hepatic resection(s). The current findings suggest that IOUS provide the most useful additional information for hepatic lesions, despite recent improvements in preoperative MRI scanning. Furthermore, routine IOUS should be employed during hepatic resection for colorectal metastases.